Engine Repair (A1)Câu 3 / 120
A valve that fails to seat fully will most directly cause which condition?
a.Low cylinder compression on that cylinder
b.Excessive oil consumption only
c.High oil pressure
d.A stuck lifter
Giải thích
A valve that does not seat allows combustion pressure to escape, lowering compression in that cylinder and often causing a misfire. A cylinder leak-down test with air hissing from the intake or exhaust confirms an intake or exhaust valve leak. Burned valves and carbon deposits are common causes.
Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
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